A trickle vent is a fitting that allows for a small flow of air into an enclosed space as a supplemental source to main ventilation systems. This kind of fitting may allow for a constant, fixed flow of air or may be adjustable and able to close completely. Trickle vents are typically built into window and door frames or skylights, although standalone fittings are also available. Control of adjustable vents is generally achieved by means of sliding flaps which progressively close the air flow aperture. Trickle vent inclusion in a ventilation system is beneficial because it allows for a constant supply of fresh air while maintaining heat retention and security.
Research has proven that the air inside most homes may be anywhere between two and five times as polluted as the outside air. Contaminants originating from solvents and cleaning materials, cooking, heating devices, pets, asbestos fittings, furniture or construction finishes, and radon can turn the air into a hazardous cocktail detrimental to occupant health. For this reason, adequate air exchange in a closed environment is essential, not only to the comfort of occupants, but to their health as well. Unfortunately, environmental issues such as heat retention during cold weather and security concerns often preclude the use of conventional means of ventilation such as doors and windows. The trickle vent offers an equitable solution in these cases, thereby allowing a constant stream of fresh air into the space while minimizing heat loss and posing no security risks.
Trickle vents are little more than small apertures designed as integral features on existing building elements or as dedicated, individual fittings. Integral vents are typically built into construction elements such as window and door frames or skylights. They are either fixed openings or include sliding or louvered flaps which allow for adjustment or closing of the vents. Many of these are fairly unobtrusive and feature color coded covers which hide the openings from view.
Dedicated trickle vent fittings are standalone elements installed through buildings walls. These fittings typically consist of a round air duct which passes through the wall and terminated on the outside by a weather- and insect-proof grill and a decorative vent on the inside. This type of trickle vent may also be fixed or adjustable and often includes internal filters to ensure the integrity of the air which enters the space. Wherever possible, these vents should ideally be place in pairs, thereby positioned in such a way to encourage cross-ventilation flow, with one serving as an entry point and the other as an exit.